There’s a number of reasons, but I’ll go through the main pro’s than means it wins out over DotNetNuke

It’s XHtml compliant out of the box, and has minimal use of tables. All the people producing skins for MojoPortal are also well evolved along the accessibility curve too.

It uses standard .NET features. This is due in no small part I’m sure to the fact that it started after DNN and more facilities were around in ASP.NET at the time. This means that Skins, Themes, Master pages are all present and correct with MojoPortal, rather than the proprietary (but well documented) skins in DNN.

It seems to be quick(er than DNN)

The facilities are stable and work very nicely. There are less modules, but the developer video tutorials are a really good way to get yourself into developing your own modules and edit pages.

You can get involved and work with the code – after downloading from SVN (I fixed a small bug and felt really good about it!)

Finally – and this is an easy clincher – the support for the product is just fantastic. Joe Audette is like a man possessed on the forums, and you’re likely to get a really well thought out answer to any query within a few hours (depending on the time zone!). He’s sorted me out on a few occasions and set me along the righteous path.

In summary, mojoPortal is something I’m happy to be using for a client as I’m more keen to use standard .NET features than proprietary skinning. I also like the philosophy more of the development community, and how Joe Audette’s running the project